首先,列出所有表: #列出所有表SHOW TABLES; 1. 2. 然后逐表执行以下代码修改字符集: #修改表的字符集ALTER TABLE 表名 CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci; 1. 2. 三、类图 White- name: String- experience: IntMySQL- version: String+changeCharacterSet(oldCharset: String,...
(1)服务器级别 ●character_set_server:服务器级别的字符集 ●collation_server:服务器级别的比较规则 如果望永久修改,则可以在MySQL配置文件的[server]选项组进行配置,示例如下 (2)数据库级别 ●character_set_database:当前数据库的字符集 ●collation_database:当前数据库的比较规则 数据库级别和表级别的都是可以...
2)查看表 show tables; desc 表; 3)修改表 alter table 表名 add 字段 类型 约束; alter table 表名 modify 字段 类型 约束; alter table 表名 change 字段 字段 类型 约束; alter table 表名 drop 字段; rename tbale 表名 to 新表名; 4)删除表 drop table 表名; 5.对数据的CRUD 1)插入数据 in...
40000 ALTER TABLE `book` ENABLE KEYS */;UNLOCKTABLES;---Table structurefortable`innodb_monitor`--DROPTABLEIFEXISTS`innodb_monitor`;/*!40101 SET @saved_cs_client = @@character_set_client */;/*!40101 SET character_set_client = utf8 */;CREATETABLE`innodb_monitor`(`a`int(11)DEFAULTNULL)E...
C. CONVERT table_name TO CHARACTER SET utf8 D. CHANGE CHARACTER SET table_name TO utf8 答案:A 10. MySQL中,哪个命令用于删除数据库? A. DROP DATABASE B. REMOVE DATABASE C. DELETE DATABASE D. DROP TABLE 答案:A 二、填空题(每题2分,共20分) 1. MySQL中,使用___命令可以查看当前连接的...
• All metadata must be in the same character set. Otherwise, neither the SHOW statements nor SELECT statements for tables in INFORMATION_SCHEMA would work properly because different rows in the same column of the results of these operations would be in different character sets. ...
ERROR3892(HY000):Currentpassword needstobe specifiedinthe REPLACE clauseinordertochange it. 正确的修改方法是使用replace带现在的密码. mysql>alteruserjerry@'localhost'identifiedby'jerry123'replace'jerrypwd'; QueryOK,0rowsaffected(0.01sec) 注意:对“mysql”系统数据库具有全局创建用户和更新权限的用户仍然可以...
错误日志中加入FLUSH TABLES WITH READ LOCK和UNLOCK TABLES日志记录,以便于线上排查问题。 性能优化 提升缓冲池初始化的性能。 Crash Recovery过程中,将未决事务的回滚由同步回滚优化为异步回滚,提升 RTO(Recovery Time Objective)。 优化AHI(Adaptive Hash Index)的内存使用和更新速度。 双向循环复制优化,备实例向主...
mysql> SHOW TABLES; +---+ | Tables_in_pets | +---+ | cats | +---+ 1 row in set (0.00 sec) DESCRIBE shows information on all columns of a table: mysql> DESCRIBE cats; +---+---+---+---+---+---+ | Field | Type | Null | Key | Default | Extra | +---+---+...
• For all Unicode collations except the _bin (binary) collations, MySQL performs a table lookup to find a character's collating weight. • For _bin collations except utf8mb4_0900_bin, the weight is based on the code point, possibly with leading zero bytes added. ...